2 % (c) The University of Glasgow 2000
5 -- --------------------------------------
6 -- The dynamic linker for GHCi
7 -- --------------------------------------
9 This module deals with the top-level issues of dynamic linking,
10 calling the object-code linker and the byte-code linker where
16 {-# OPTIONS -optc-DNON_POSIX_SOURCE -#include "Linker.h" #-}
18 module Linker ( HValue, showLinkerState,
19 linkExpr, unload, extendLinkEnv,
23 #include "../includes/ghcconfig.h"
24 #include "HsVersions.h"
26 import ObjLink ( loadDLL, loadObj, unloadObj, resolveObjs, initObjLinker )
27 import ByteCodeLink ( HValue, ClosureEnv, extendClosureEnv, linkBCO )
28 import ByteCodeItbls ( ItblEnv )
29 import ByteCodeAsm ( CompiledByteCode(..), bcoFreeNames, UnlinkedBCO(..))
32 import DriverState ( v_Library_paths, v_Opt_l, v_Ld_inputs, getStaticOpts )
33 import DriverPhases ( isObjectFilename, isDynLibFilename )
34 import DriverUtil ( getFileSuffix )
35 #ifdef darwin_TARGET_OS
36 import DriverState ( v_Cmdline_frameworks, v_Framework_paths )
38 import Finder ( findModule, findLinkable, FindResult(..) )
40 import Name ( Name, nameModule, isExternalName, isWiredInName )
42 import NameSet ( nameSetToList )
44 import ListSetOps ( minusList )
45 import CmdLineOpts ( DynFlags(..) )
46 import BasicTypes ( SuccessFlag(..), succeeded, failed )
48 import Panic ( GhcException(..) )
49 import Util ( zipLazy, global )
52 import Control.Monad ( when, filterM, foldM )
54 import Data.IORef ( IORef, readIORef, writeIORef )
55 import Data.List ( partition, nub )
57 import System.IO ( putStr, putStrLn, hPutStrLn, stderr, fixIO )
58 import System.Directory ( doesFileExist )
60 import Control.Exception ( block, throwDyn )
62 #if __GLASGOW_HASKELL__ >= 503
63 import GHC.IOBase ( IO(..) )
65 import PrelIOBase ( IO(..) )
70 %************************************************************************
74 %************************************************************************
76 The persistent linker state *must* match the actual state of the
77 C dynamic linker at all times, so we keep it in a private global variable.
80 The PersistentLinkerState maps Names to actual closures (for
81 interpreted code only), for use during linking.
84 GLOBAL_VAR(v_PersistentLinkerState, panic "Dynamic linker not initialised", PersistentLinkerState)
85 GLOBAL_VAR(v_InitLinkerDone, False, Bool) -- Set True when dynamic linker is initialised
87 data PersistentLinkerState
88 = PersistentLinkerState {
90 -- Current global mapping from Names to their true values
91 closure_env :: ClosureEnv,
93 -- The current global mapping from RdrNames of DataCons to
94 -- info table addresses.
95 -- When a new Unlinked is linked into the running image, or an existing
96 -- module in the image is replaced, the itbl_env must be updated
100 -- The currently loaded interpreted modules (home package)
101 bcos_loaded :: [Linkable],
103 -- And the currently-loaded compiled modules (home package)
104 objs_loaded :: [Linkable],
106 -- The currently-loaded packages; always object code
107 -- Held, as usual, in dependency order; though I am not sure if
108 -- that is really important
109 pkgs_loaded :: [PackageId]
112 emptyPLS :: DynFlags -> PersistentLinkerState
113 emptyPLS dflags = PersistentLinkerState {
114 closure_env = emptyNameEnv,
115 itbl_env = emptyNameEnv,
116 pkgs_loaded = init_pkgs,
119 -- Packages that don't need loading, because the compiler
120 -- shares them with the interpreted program.
122 -- The linker's symbol table is populated with RTS symbols using an
123 -- explicit list. See rts/Linker.c for details.
125 | Just rts_id <- rtsPackageId (pkgState dflags) = [rts_id]
131 extendLinkEnv :: [(Name,HValue)] -> IO ()
132 -- Automatically discards shadowed bindings
133 extendLinkEnv new_bindings
134 = do pls <- readIORef v_PersistentLinkerState
135 let new_closure_env = extendClosureEnv (closure_env pls) new_bindings
136 new_pls = pls { closure_env = new_closure_env }
137 writeIORef v_PersistentLinkerState new_pls
139 -- filterNameMap removes from the environment all entries except
140 -- those for a given set of modules;
141 -- Note that this removes all *local* (i.e. non-isExternal) names too
142 -- (these are the temporary bindings from the command line).
143 -- Used to filter both the ClosureEnv and ItblEnv
145 filterNameMap :: [Module] -> NameEnv (Name, a) -> NameEnv (Name, a)
146 filterNameMap mods env
147 = filterNameEnv keep_elt env
149 keep_elt (n,_) = isExternalName n
150 && (nameModule n `elem` mods)
155 showLinkerState :: IO ()
156 -- Display the persistent linker state
158 = do pls <- readIORef v_PersistentLinkerState
159 printDump (vcat [text "----- Linker state -----",
160 text "Pkgs:" <+> ppr (pkgs_loaded pls),
161 text "Objs:" <+> ppr (objs_loaded pls),
162 text "BCOs:" <+> ppr (bcos_loaded pls)])
168 %************************************************************************
170 \subsection{Initialisation}
172 %************************************************************************
174 We initialise the dynamic linker by
176 a) calling the C initialisation procedure
178 b) Loading any packages specified on the command line,
179 now held in v_ExplicitPackages
181 c) Loading any packages specified on the command line,
182 now held in the -l options in v_Opt_l
184 d) Loading any .o/.dll files specified on the command line,
185 now held in v_Ld_inputs
187 e) Loading any MacOS frameworks
190 initDynLinker :: DynFlags -> IO ()
191 -- This function is idempotent; if called more than once, it does nothing
192 -- This is useful in Template Haskell, where we call it before trying to link
194 = do { done <- readIORef v_InitLinkerDone
195 ; if done then return ()
196 else do { writeIORef v_InitLinkerDone True
197 ; reallyInitDynLinker dflags }
200 reallyInitDynLinker dflags
201 = do { -- Initialise the linker state
202 ; writeIORef v_PersistentLinkerState (emptyPLS dflags)
204 -- (a) initialise the C dynamic linker
207 -- (b) Load packages from the command-line
208 ; linkPackages dflags (explicitPackages (pkgState dflags))
210 -- (c) Link libraries from the command-line
211 ; opt_l <- getStaticOpts v_Opt_l
212 ; let minus_ls = [ lib | '-':'l':lib <- opt_l ]
214 -- (d) Link .o files from the command-line
215 ; lib_paths <- readIORef v_Library_paths
216 ; cmdline_ld_inputs <- readIORef v_Ld_inputs
218 ; classified_ld_inputs <- mapM classifyLdInput cmdline_ld_inputs
220 -- (e) Link any MacOS frameworks
221 #ifdef darwin_TARGET_OS
222 ; framework_paths <- readIORef v_Framework_paths
223 ; frameworks <- readIORef v_Cmdline_frameworks
225 ; let frameworks = []
226 ; let framework_paths = []
228 -- Finally do (c),(d),(e)
229 ; let cmdline_lib_specs = [ l | Just l <- classified_ld_inputs ]
231 ++ map Framework frameworks
232 ; if null cmdline_lib_specs then return ()
235 { mapM_ (preloadLib dflags lib_paths framework_paths) cmdline_lib_specs
236 ; maybePutStr dflags "final link ... "
239 ; if succeeded ok then maybePutStrLn dflags "done"
240 else throwDyn (InstallationError "linking extra libraries/objects failed")
243 classifyLdInput :: FilePath -> IO (Maybe LibrarySpec)
245 | isObjectFilename f = return (Just (Object f))
246 | isDynLibFilename f = return (Just (DLLPath f))
248 hPutStrLn stderr ("Warning: ignoring unrecognised input `" ++ f ++ "'")
251 preloadLib :: DynFlags -> [String] -> [String] -> LibrarySpec -> IO ()
252 preloadLib dflags lib_paths framework_paths lib_spec
253 = do maybePutStr dflags ("Loading object " ++ showLS lib_spec ++ " ... ")
256 -> do b <- preload_static lib_paths static_ish
257 maybePutStrLn dflags (if b then "done"
261 -> do maybe_errstr <- loadDynamic lib_paths dll_unadorned
263 Nothing -> maybePutStrLn dflags "done"
264 Just mm -> preloadFailed mm lib_paths lib_spec
267 -> do maybe_errstr <- loadDLL dll_path
269 Nothing -> maybePutStrLn dflags "done"
270 Just mm -> preloadFailed mm lib_paths lib_spec
272 #ifdef darwin_TARGET_OS
274 -> do maybe_errstr <- loadFramework framework_paths framework
276 Nothing -> maybePutStrLn dflags "done"
277 Just mm -> preloadFailed mm framework_paths lib_spec
280 preloadFailed :: String -> [String] -> LibrarySpec -> IO ()
281 preloadFailed sys_errmsg paths spec
282 = do maybePutStr dflags
283 ("failed.\nDynamic linker error message was:\n "
284 ++ sys_errmsg ++ "\nWhilst trying to load: "
285 ++ showLS spec ++ "\nDirectories to search are:\n"
286 ++ unlines (map (" "++) paths) )
289 -- Not interested in the paths in the static case.
290 preload_static paths name
291 = do b <- doesFileExist name
292 if not b then return False
293 else loadObj name >> return True
296 CmdLineError "user specified .o/.so/.DLL could not be loaded."
300 %************************************************************************
302 Link a byte-code expression
304 %************************************************************************
307 linkExpr :: HscEnv -> UnlinkedBCO -> IO HValue
309 -- Link a single expression, *including* first linking packages and
310 -- modules that this expression depends on.
312 -- Raises an IO exception if it can't find a compiled version of the
313 -- dependents to link.
315 linkExpr hsc_env root_ul_bco
317 -- Initialise the linker (if it's not been done already)
318 let dflags = hsc_dflags hsc_env
319 ; initDynLinker dflags
321 -- Find what packages and linkables are required
322 ; eps <- readIORef (hsc_EPS hsc_env)
323 ; (lnks, pkgs) <- getLinkDeps dflags hpt (eps_PIT eps) needed_mods
325 -- Link the packages and modules required
326 ; linkPackages dflags pkgs
327 ; ok <- linkModules dflags lnks
332 -- Link the expression itself
333 pls <- readIORef v_PersistentLinkerState
334 ; let ie = itbl_env pls
337 -- Link the necessary packages and linkables
338 ; (_, (root_hval:_)) <- linkSomeBCOs False ie ce [root_ul_bco]
342 hpt = hsc_HPT hsc_env
343 dflags = hsc_dflags hsc_env
344 free_names = nameSetToList (bcoFreeNames root_ul_bco)
346 needed_mods :: [Module]
347 needed_mods = [ nameModule n | n <- free_names,
348 isExternalName n, -- Names from other modules
349 not (isWiredInName n) -- Exclude wired-in names
350 ] -- (see note below)
351 -- Exclude wired-in names because we may not have read
352 -- their interface files, so getLinkDeps will fail
353 -- All wired-in names are in the base package, which we link
354 -- by default, so we can safely ignore them here.
356 dieWith msg = throwDyn (ProgramError (showSDoc msg))
358 getLinkDeps :: DynFlags -> HomePackageTable -> PackageIfaceTable
359 -> [Module] -- If you need these
360 -> IO ([Linkable], [PackageId]) -- ... then link these first
361 -- Fails with an IO exception if it can't find enough files
363 getLinkDeps dflags hpt pit mods
364 -- Find all the packages and linkables that a set of modules depends on
365 = do { pls <- readIORef v_PersistentLinkerState ;
367 -- 1. Find the dependent home-pkg-modules/packages from each iface
368 (mods_s, pkgs_s) = unzip (map get_deps mods) ;
370 -- 2. Exclude ones already linked
371 -- Main reason: avoid findModule calls in get_linkable
372 mods_needed = nub (concat mods_s) `minusList` linked_mods ;
373 pkgs_needed = nub (concat pkgs_s) `minusList` pkgs_loaded pls ;
375 linked_mods = map linkableModule (objs_loaded pls ++ bcos_loaded pls)
378 -- 3. For each dependent module, find its linkable
379 -- This will either be in the HPT or (in the case of one-shot
380 -- compilation) we may need to use maybe_getFileLinkable
381 lnks_needed <- mapM get_linkable mods_needed ;
383 return (lnks_needed, pkgs_needed) }
385 get_deps :: Module -> ([Module],[PackageId])
386 -- Get the things needed for the specified module
387 -- This is rather similar to the code in RnNames.importsFromImportDecl
389 | ExternalPackage p <- mi_package iface
390 = ([], p : dep_pkgs deps)
392 = (mod : [m | (m,_) <- dep_mods deps], dep_pkgs deps)
394 iface = get_iface mod
397 get_iface mod = case lookupIface hpt pit mod of
399 Nothing -> pprPanic "getLinkDeps" (no_iface mod)
400 no_iface mod = ptext SLIT("No iface for") <+> ppr mod
401 -- This one is a GHC bug
403 no_obj mod = dieWith (ptext SLIT("No compiled code for") <+> ppr mod)
404 -- This one is a build-system bug
406 get_linkable mod_name -- A home-package module
407 | Just mod_info <- lookupModuleEnv hpt mod_name
408 = return (hm_linkable mod_info)
410 = -- It's not in the HPT because we are in one shot mode,
411 -- so use the Finder to get a ModLocation...
412 do { mb_stuff <- findModule dflags mod_name False ;
414 Found loc _ -> found loc mod_name ;
418 found loc mod_name = do {
419 -- ...and then find the linkable for it
420 mb_lnk <- findLinkable mod_name loc ;
422 Nothing -> no_obj mod_name ;
423 Just lnk -> return lnk
428 %************************************************************************
431 The linkables may consist of a mixture of
432 byte-code modules and object modules
434 %************************************************************************
437 linkModules :: DynFlags -> [Linkable] -> IO SuccessFlag
438 linkModules dflags linkables
439 = block $ do -- don't want to be interrupted by ^C in here
441 let (objs, bcos) = partition isObjectLinkable
442 (concatMap partitionLinkable linkables)
444 -- Load objects first; they can't depend on BCOs
445 ok_flag <- dynLinkObjs dflags objs
447 if failed ok_flag then
454 -- HACK to support f-x-dynamic in the interpreter; no other purpose
455 partitionLinkable :: Linkable -> [Linkable]
457 = let li_uls = linkableUnlinked li
458 li_uls_obj = filter isObject li_uls
459 li_uls_bco = filter isInterpretable li_uls
461 case (li_uls_obj, li_uls_bco) of
462 (objs@(_:_), bcos@(_:_))
463 -> [li{linkableUnlinked=li_uls_obj}, li{linkableUnlinked=li_uls_bco}]
467 findModuleLinkable_maybe :: [Linkable] -> Module -> Maybe Linkable
468 findModuleLinkable_maybe lis mod
469 = case [LM time nm us | LM time nm us <- lis, nm == mod] of
472 many -> pprPanic "findModuleLinkable" (ppr mod)
474 linkableInSet :: Linkable -> [Linkable] -> Bool
475 linkableInSet l objs_loaded =
476 case findModuleLinkable_maybe objs_loaded (linkableModule l) of
478 Just m -> linkableTime l == linkableTime m
482 %************************************************************************
484 \subsection{The object-code linker}
486 %************************************************************************
489 dynLinkObjs :: DynFlags -> [Linkable] -> IO SuccessFlag
490 -- Side-effects the PersistentLinkerState
492 dynLinkObjs dflags objs
493 = do pls <- readIORef v_PersistentLinkerState
495 -- Load the object files and link them
496 let (objs_loaded', new_objs) = rmDupLinkables (objs_loaded pls) objs
497 pls1 = pls { objs_loaded = objs_loaded' }
498 unlinkeds = concatMap linkableUnlinked new_objs
500 mapM loadObj (map nameOfObject unlinkeds)
502 -- Link the all together
505 -- If resolving failed, unload all our
506 -- object modules and carry on
507 if succeeded ok then do
508 writeIORef v_PersistentLinkerState pls1
511 pls2 <- unload_wkr dflags [] pls1
512 writeIORef v_PersistentLinkerState pls2
516 rmDupLinkables :: [Linkable] -- Already loaded
517 -> [Linkable] -- New linkables
518 -> ([Linkable], -- New loaded set (including new ones)
519 [Linkable]) -- New linkables (excluding dups)
520 rmDupLinkables already ls
523 go already extras [] = (already, extras)
524 go already extras (l:ls)
525 | linkableInSet l already = go already extras ls
526 | otherwise = go (l:already) (l:extras) ls
529 %************************************************************************
531 \subsection{The byte-code linker}
533 %************************************************************************
536 dynLinkBCOs :: [Linkable] -> IO ()
537 -- Side-effects the persistent linker state
539 = do pls <- readIORef v_PersistentLinkerState
541 let (bcos_loaded', new_bcos) = rmDupLinkables (bcos_loaded pls) bcos
542 pls1 = pls { bcos_loaded = bcos_loaded' }
543 unlinkeds :: [Unlinked]
544 unlinkeds = concatMap linkableUnlinked new_bcos
546 cbcs :: [CompiledByteCode]
547 cbcs = map byteCodeOfObject unlinkeds
550 ul_bcos = [b | ByteCode bs _ <- cbcs, b <- bs]
551 ies = [ie | ByteCode _ ie <- cbcs]
552 gce = closure_env pls
553 final_ie = foldr plusNameEnv (itbl_env pls) ies
555 (final_gce, linked_bcos) <- linkSomeBCOs True final_ie gce ul_bcos
556 -- What happens to these linked_bcos?
558 let pls2 = pls1 { closure_env = final_gce,
559 itbl_env = final_ie }
561 writeIORef v_PersistentLinkerState pls2
564 -- Link a bunch of BCOs and return them + updated closure env.
565 linkSomeBCOs :: Bool -- False <=> add _all_ BCOs to returned closure env
566 -- True <=> add only toplevel BCOs to closure env
570 -> IO (ClosureEnv, [HValue])
571 -- The returned HValues are associated 1-1 with
572 -- the incoming unlinked BCOs. Each gives the
573 -- value of the corresponding unlinked BCO
576 linkSomeBCOs toplevs_only ie ce_in ul_bcos
577 = do let nms = map unlinkedBCOName ul_bcos
579 ( \ hvs -> let ce_out = extendClosureEnv ce_in (zipLazy nms hvs)
580 in mapM (linkBCO ie ce_out) ul_bcos )
582 let ce_all_additions = zip nms hvals
583 ce_top_additions = filter (isExternalName.fst) ce_all_additions
584 ce_additions = if toplevs_only then ce_top_additions
585 else ce_all_additions
586 ce_out = -- make sure we're not inserting duplicate names into the
587 -- closure environment, which leads to trouble.
588 ASSERT (all (not . (`elemNameEnv` ce_in)) (map fst ce_additions))
589 extendClosureEnv ce_in ce_additions
590 return (ce_out, hvals)
595 %************************************************************************
597 Unload some object modules
599 %************************************************************************
602 -- ---------------------------------------------------------------------------
603 -- Unloading old objects ready for a new compilation sweep.
605 -- The compilation manager provides us with a list of linkables that it
606 -- considers "stable", i.e. won't be recompiled this time around. For
607 -- each of the modules current linked in memory,
609 -- * if the linkable is stable (and it's the same one - the
610 -- user may have recompiled the module on the side), we keep it,
612 -- * otherwise, we unload it.
614 -- * we also implicitly unload all temporary bindings at this point.
616 unload :: DynFlags -> [Linkable] -> IO ()
617 -- The 'linkables' are the ones to *keep*
619 unload dflags linkables
620 = block $ do -- block, so we're safe from Ctrl-C in here
622 pls <- readIORef v_PersistentLinkerState
623 new_pls <- unload_wkr dflags linkables pls
624 writeIORef v_PersistentLinkerState new_pls
626 let verb = verbosity dflags
627 when (verb >= 3) $ do
628 hPutStrLn stderr (showSDoc
629 (text "unload: retaining objs" <+> ppr (objs_loaded new_pls)))
630 hPutStrLn stderr (showSDoc
631 (text "unload: retaining bcos" <+> ppr (bcos_loaded new_pls)))
635 unload_wkr :: DynFlags
636 -> [Linkable] -- stable linkables
637 -> PersistentLinkerState
638 -> IO PersistentLinkerState
639 -- Does the core unload business
640 -- (the wrapper blocks exceptions and deals with the PLS get and put)
642 unload_wkr dflags linkables pls
643 = do let (objs_to_keep, bcos_to_keep) = partition isObjectLinkable linkables
645 objs_loaded' <- filterM (maybeUnload objs_to_keep) (objs_loaded pls)
646 bcos_loaded' <- filterM (maybeUnload bcos_to_keep) (bcos_loaded pls)
648 let bcos_retained = map linkableModule bcos_loaded'
649 itbl_env' = filterNameMap bcos_retained (itbl_env pls)
650 closure_env' = filterNameMap bcos_retained (closure_env pls)
651 new_pls = pls { itbl_env = itbl_env',
652 closure_env = closure_env',
653 bcos_loaded = bcos_loaded',
654 objs_loaded = objs_loaded' }
658 maybeUnload :: [Linkable] -> Linkable -> IO Bool
659 maybeUnload keep_linkables lnk
660 | linkableInSet lnk linkables = return True
662 = do mapM_ unloadObj [f | DotO f <- linkableUnlinked lnk]
663 -- The components of a BCO linkable may contain
664 -- dot-o files. Which is very confusing.
666 -- But the BCO parts can be unlinked just by
667 -- letting go of them (plus of course depopulating
668 -- the symbol table which is done in the main body)
673 %************************************************************************
677 %************************************************************************
682 = Object FilePath -- Full path name of a .o file, including trailing .o
683 -- For dynamic objects only, try to find the object
684 -- file in all the directories specified in
685 -- v_Library_paths before giving up.
687 | DLL String -- "Unadorned" name of a .DLL/.so
688 -- e.g. On unix "qt" denotes "libqt.so"
689 -- On WinDoze "burble" denotes "burble.DLL"
690 -- loadDLL is platform-specific and adds the lib/.so/.DLL
691 -- suffixes platform-dependently
693 | DLLPath FilePath -- Absolute or relative pathname to a dynamic library
694 -- (ends with .dll or .so).
696 | Framework String -- Only used for darwin, but does no harm
698 -- If this package is already part of the GHCi binary, we'll already
699 -- have the right DLLs for this package loaded, so don't try to
702 -- But on Win32 we must load them 'again'; doing so is a harmless no-op
703 -- as far as the loader is concerned, but it does initialise the list
704 -- of DLL handles that rts/Linker.c maintains, and that in turn is
705 -- used by lookupSymbol. So we must call addDLL for each library
706 -- just to get the DLL handle into the list.
708 # if defined(mingw32_TARGET_OS) || defined(darwin_TARGET_OS)
711 = [ "base", "haskell98", "template-haskell", "readline" ]
714 showLS (Object nm) = "(static) " ++ nm
715 showLS (DLL nm) = "(dynamic) " ++ nm
716 showLS (DLLPath nm) = "(dynamic) " ++ nm
717 showLS (Framework nm) = "(framework) " ++ nm
719 linkPackages :: DynFlags -> [PackageId] -> IO ()
720 -- Link exactly the specified packages, and their dependents
721 -- (unless of course they are already linked)
722 -- The dependents are linked automatically, and it doesn't matter
723 -- what order you specify the input packages.
725 -- NOTE: in fact, since each module tracks all the packages it depends on,
726 -- we don't really need to use the package-config dependencies.
727 -- However we do need the package-config stuff (to find aux libs etc),
728 -- and following them lets us load libraries in the right order, which
729 -- perhaps makes the error message a bit more localised if we get a link
730 -- failure. So the dependency walking code is still here.
732 linkPackages dflags new_pkgs
733 = do { pls <- readIORef v_PersistentLinkerState
734 ; let pkg_map = pkgIdMap (pkgState dflags)
736 ; pkgs' <- link pkg_map (pkgs_loaded pls) new_pkgs
738 ; writeIORef v_PersistentLinkerState (pls { pkgs_loaded = pkgs' })
741 link :: PackageConfigMap -> [PackageId] -> [PackageId] -> IO [PackageId]
742 link pkg_map pkgs new_pkgs
743 = foldM (link_one pkg_map) pkgs new_pkgs
745 link_one pkg_map pkgs new_pkg
746 | new_pkg `elem` pkgs -- Already linked
749 | Just pkg_cfg <- lookupPackage pkg_map new_pkg
750 = do { -- Link dependents first
751 pkgs' <- link pkg_map pkgs (map mkPackageId (depends pkg_cfg))
752 -- Now link the package itself
753 ; linkPackage dflags pkg_cfg
754 ; return (new_pkg : pkgs') }
757 = throwDyn (CmdLineError ("unknown package: " ++ packageIdString new_pkg))
760 linkPackage :: DynFlags -> PackageConfig -> IO ()
761 linkPackage dflags pkg
763 let dirs = Packages.libraryDirs pkg
764 let libs = Packages.hsLibraries pkg ++ Packages.extraLibraries pkg
765 ++ [ lib | '-':'l':lib <- Packages.extraLdOpts pkg ]
766 classifieds <- mapM (locateOneObj dirs) libs
768 -- Complication: all the .so's must be loaded before any of the .o's.
769 let dlls = [ dll | DLL dll <- classifieds ]
770 objs = [ obj | Object obj <- classifieds ]
772 maybePutStr dflags ("Loading package " ++ showPackageId (package pkg) ++ " ... ")
774 -- See comments with partOfGHCi
775 when (pkgName (package pkg) `notElem` partOfGHCi) $ do
777 -- When a library A needs symbols from a library B, the order in
778 -- extra_libraries/extra_ld_opts is "-lA -lB", because that's the
779 -- way ld expects it for static linking. Dynamic linking is a
780 -- different story: When A has no dependency information for B,
781 -- dlopen-ing A with RTLD_NOW (see addDLL in Linker.c) will fail
782 -- when B has not been loaded before. In a nutshell: Reverse the
783 -- order of DLLs for dynamic linking.
784 -- This fixes a problem with the HOpenGL package (see "Compiling
785 -- HOpenGL under recent versions of GHC" on the HOpenGL list).
786 mapM_ (load_dyn dirs) (reverse dlls)
788 -- After loading all the DLLs, we can load the static objects.
789 -- Ordering isn't important here, because we do one final link
790 -- step to resolve everything.
793 maybePutStr dflags "linking ... "
795 if succeeded ok then maybePutStrLn dflags "done."
796 else throwDyn (InstallationError ("unable to load package `" ++ showPackageId (package pkg) ++ "'"))
798 load_dyn dirs dll = do r <- loadDynamic dirs dll
801 Just err -> throwDyn (CmdLineError ("can't load .so/.DLL for: "
802 ++ dll ++ " (" ++ err ++ ")" ))
803 #ifndef darwin_TARGET_OS
804 loadFrameworks pkg = return ()
806 loadFrameworks pkg = mapM_ load frameworks
808 fw_dirs = Packages.frameworkDirs pkg
809 frameworks = Packages.extraFrameworks pkg
811 load fw = do r <- loadFramework fw_dirs fw
814 Just err -> throwDyn (CmdLineError ("can't load framework: "
815 ++ fw ++ " (" ++ err ++ ")" ))
818 -- Try to find an object file for a given library in the given paths.
819 -- If it isn't present, we assume it's a dynamic library.
820 locateOneObj :: [FilePath] -> String -> IO LibrarySpec
821 locateOneObj dirs lib
822 = do { mb_obj_path <- findFile mk_obj_path dirs
823 ; case mb_obj_path of
824 Just obj_path -> return (Object obj_path)
825 Nothing -> return (DLL lib) } -- We assume
827 mk_obj_path dir = dir ++ '/':lib ++ ".o"
830 -- ----------------------------------------------------------------------------
831 -- Loading a dyanmic library (dlopen()-ish on Unix, LoadLibrary-ish on Win32)
833 -- return Nothing == success, else Just error message from dlopen
834 loadDynamic paths rootname
835 = do { mb_dll <- findFile mk_dll_path paths
837 Just dll -> loadDLL dll
838 Nothing -> loadDLL (mkSOName rootname) }
839 -- Tried all our known library paths, so let
840 -- dlopen() search its own builtin paths now.
842 mk_dll_path dir = dir ++ '/':mkSOName rootname
844 #if defined(darwin_TARGET_OS)
845 mkSOName root = "lib" ++ root ++ ".dylib"
846 #elif defined(mingw32_TARGET_OS)
847 -- Win32 DLLs have no .dll extension here, because addDLL tries
848 -- both foo.dll and foo.drv
851 mkSOName root = "lib" ++ root ++ ".so"
854 -- Darwin / MacOS X only: load a framework
855 -- a framework is a dynamic library packaged inside a directory of the same
856 -- name. They are searched for in different paths than normal libraries.
857 #ifdef darwin_TARGET_OS
858 loadFramework extraPaths rootname
859 = do { mb_fwk <- findFile mk_fwk (extraPaths ++ defaultFrameworkPaths)
861 Just fwk_path -> loadDLL fwk_path
862 Nothing -> return (Just "not found") }
863 -- Tried all our known library paths, but dlopen()
864 -- has no built-in paths for frameworks: give up
866 mk_fwk dir = dir ++ '/' : rootname ++ ".framework/" ++ rootname
867 -- sorry for the hardcoded paths, I hope they won't change anytime soon:
868 defaultFrameworkPaths = ["/Library/Frameworks", "/System/Library/Frameworks"]
872 %************************************************************************
876 %************************************************************************
879 findFile :: (FilePath -> FilePath) -- Maps a directory path to a file path
880 -> [FilePath] -- Directories to look in
881 -> IO (Maybe FilePath) -- The first file path to match
882 findFile mk_file_path []
884 findFile mk_file_path (dir:dirs)
885 = do { let file_path = mk_file_path dir
886 ; b <- doesFileExist file_path
888 return (Just file_path)
890 findFile mk_file_path dirs }
894 maybePutStr dflags s | verbosity dflags > 0 = putStr s
895 | otherwise = return ()
897 maybePutStrLn dflags s | verbosity dflags > 0 = putStrLn s
898 | otherwise = return ()